Cells Become Differentiated and Somatized 83 



possible to put it in conditions which would render it 

 capable of nourishing itself and preserving its life 

 independently separated from the rest of the organism, 

 could function as a germ cell. 53 



And certain processes which appear in all the lower 

 organisms, with tissues that are not very highly 

 specialized, appear to justify this view. 



If one places a piece of a Begonia phyllomaniaca in 

 some earth in moist air, after cutting through the leaf- 

 ribs in different places, one finds after some time, in the 

 neighborhood of each wound, one or more little new 

 plants. Any fragment whatever of a hydra or medusa 

 possesses the power of reforming an entire animal 

 without increasing its mass, but rather by a process of 

 differentiation and rearrangement of cells already existing. 



A theory which admits equal nuclear division and also 

 a slow and gradual nuclear somatization, resulting from 

 the action of a determinate zone constituted only by the 

 germinal substance, would reconcile the different and 

 contradictory phenomena brought forward by the epi- 

 genesists on the one side, and by the preformists on the 

 other. 



Oscar Hertwig who as we have just seen is a zealous 

 partisan of the idioplasmic equality of all nuclei, is com- 

 mitted in another place to the possibility of a certain 

 nuclear somatization. "The hypothesis of a hereditarily 

 equal nuclear division does not imply the view that the 

 'anlage' substance must therefore be an immutable 

 thing. . . . The idioplasms of certain groups of cells 

 of an organism which find themselves permanently in 

 unlike conditions in consequence of their different spatial 

 and functional disposition in the body as a whole, dif- 



"Oscar Hertwig: Die Zelle und die Gewebe. Zw. Buch. P, 

 304305. 



